提出了一种基于接收方数据流驱动的标签分配机制构建MPLS域中LSP组播树的方案,给出了MPLS网络中成员加入和退出组播组以及组播包的复制和转发算法。并且对网络仿真工具NS的MPLS模块进行扩展以支持所提出的组播算法。性能分析和仿真实验结果表明：与传统组播相比,MPLS的组播技术能利用MPLS的快速转发能力有效地减少组播包的传输时延。 This paper proposes a scheme of constructing LSP multicast tree in MPLS domain based on the label-driven mechanism driven by receiver data stream. The algorithm of replication and forwarding of members joining and exiting multicast groups and multicast packets in MPLS network is given. And extends the MPLS module of the network simulation tool NS to support the proposed multicast algorithm. Performance analysis and simulation results show that: Compared with the traditional multicast, MPLS multicast technology can take advantage of the fast forwarding capability of MPLS to effectively reduce the transmission delay of multicast packets.